apply given patches for ruby sources

Author: kateinoigakukun

Rakefile

@@ -13,7 +13,7 @@ BUILD_SOURCES = {
     type: "github",
     repo: "ruby/ruby",
     rev: "master",
-    patches: []
+    patches: Dir["./patches/*.patch"].map{|p| File.expand_path(p) }
   }
 }
 

lib/ruby_wasm/build_system/product/ruby_source.rb

@@ -34,6 +34,9 @@ def fetch
       else
         raise "unknown source type: #{@params[:type]}"
       end
+      (@params[:patches] || []).each do |patch_path|
+        system "patch -p1 < #{patch_path}", chdir: src_dir
+      end
     end
 
     def build